Drill-chuck.



FRANK COBEY, OF EAST BERLIN, CONNECTICUT.

DRILL-CHCK,

To all whom t'may concern:

Be it known that I,AFRANK COBEY, a citizen vofthe United lvStates, residing at East Berlin, in thefcounty of Hartfordv and State of' Connecticut, have invented certain new andfuseful Improvements in Drill-Chucks, of which 4the following is a specification.

My invention-relates to improvements in drill chucks, and theobject of myimprovementis simplicity and economy in construction and `convenience and eliciency in use.

In lthe laccompanying drawingF-Figure 1 is a yside elevation of my improved drill chuck. Fig. 2 is an end elevation of the same. Fig. 3 is a sectional view, on an enlarged scale, on the line rc w of Fig. 2. Fig.'

4 is a similar view of the casing, the other parts being shown in side elevation. Fig. 5 is a side elevationof the inner cam member.

Fig.l 6 is a similar view of the spindle mem-.

bel. Fig 7 .is a lsimilar viewof the outer cam member.

My improved drill chuck comprises a spindle member 10 on the outer end of which is mounted a shell 11 having inclined Ways 12 at the outer enclin which are positioned jaws- 13, andmechanism interconnecting the said spindle member, shell, and jaws whereby turning ythe shell relatively to the spindle member serves to open and close the jaws.

" The shell 11 is made of two parts, connected by a screw thread connection 14.

v The inner end of the spindle member may be provided with a. recessl for an arbor or spindle.

The outer end `of the spindle member 10 has a. circular recess 16, forming a disk-like head 17 at the extreme outer end suitable to engage with the inner ends of the jaws 13, which are formed each with an inwardly directed lug recess 16 and head 17.

The spindle member 10 is provided on the periphery of the body portion with ,a .screw thread 20 that is relatively fine. The. sp1ndle member 10 is furthermore provided with a. radial pin 2 1, positioned preferably at some part of the body portion traversed byl the thread 20.

Intermediate the spindle member 10 and the shell 11 there is a space that is Ifilled, by two cooperating sleeve members, respectively an inner sleeve member 22 and an -eiitersleeve member 23, which have opposededges 27 in abutment and formed as a single turn helix, or screw thread, of relatively- Specification of Letters Patent.

18 and a recess 19 fitting the said.

intente Nov. 1e, 1915.

'Application `filed December 7, 1914. SerialNb. 875,851.

steep pitch, and in the same direction of inclination on the axis as the thread 21,` being both shown as right hande f The inner sleeve member 22 is secured in the rear or base portion of the shell- 11 by a screw thread connection 24, a flange 25 `at the extreme inner end being inv abutment with the inner end of the shell 11, so that the same is operatively fixed to the shell A11',v

and the same is provided with an axial 'bore 26 that is a fit for the body portion of the spindle member 10.

The outer sleeve member 23 has an inter- 'nal thread 28 that is a t for the thread 20 on the body portion of the spindle member 10 and `is held on the said spindle" member 10 by means of a hole 4orvslot 29 engaged with tle pin 21.

By providing a slot 29 in which the said pin may have a limited lateral movement in lieu of a hole that is a .close fit-for the pin the outer sleeve member 23 has a limited roy `tative movement on the spindle member. 10 that I Iind to be of advantage in effectingI .the final clamping on the stock, and this is the preferred construction.

In operation, turning the shell '11 relatively to the spindle member 10 operates to turn the aws, the inner ends of the latter being free to turn under pressure relatively to the head portion .of the spindle member, and serves to change the relative position of the sleeve members 22 and 23, due to the en'- gagementl of these members along the outer, larger or coarser thread 27. *The engagement of the sleeve members22 and 23 as described serves to elfect a relative longitudinal movement of the spindle member 10 and the shell'll, and this movement will be relativelyl great, due to the large pitch of the outer or shell thread 27. That is to say that a lsmall angular movement operates to effeet a relatively large longitudinal movement, and a correspondingly great movement of the jaws, either in opening or closing, depending upon the particular direction of the turning movement. l During such turning, assuming the direction of the same to' be right handed, so as to effect a closing of the jaws, the pin 21v will be in abutment with what may be termed .the rear wall 30 of the slot 29, and is moved along the slot 29 in effecting the inal grip. A reversal of the movement described serves to draw the pin 21 away from the rear wall 30, slightly corresponding to a slight movement of the cordingly, a relatively quickv and largemovement o'f the-'shell and spindle,memberis'zeffected, Vresulting in 4ment of the jaws', Which-result is dueto the 'effect of the large or coarse thread 2'( on the two opposed sleeve members.

-The,1nner sleeve member 22 constitutes essentially a xed part of the shell 11 and 15 ,the outer sleeve member l23 constitutes essen- -ti'ally lan enlargement of the body. portion of the spindle member, theparticular means of construction. shown and described being simply one method of effecting the result 20 mentioned, and other forms of construction the appended .claims ber, sleeve members filling the space betweenjo the said shell and 'spindle member, one of 4*within the scope of may be used in some cases..

One-way of describing theoperation of my drill 'chuck is tol say that the. coarse thread makesup the distance andthe fine- .thread -is used for eifecting the inaltightening. In the irst.moen1e-ntxl Zin-malng up the distance and before there is a gripping of the ,work there is no turning movement member, but after the gripping of the Work by. thejaws the resistance to longitudinal movement due tothe gripping of the work opferatesiin combination with the continued turning of clamping to turn the outer sleeve member on thespindle member, due to the engagement oflv the coarse thread portions of the two sleeve 'members, and during which -move- 40 ment the pin creeps away from theshoulder, traveling in the slot until the final gripping kor clamping is elected. In gaining the distance as described the longitudinally directed shoulders 31 on the sleeve members become separated, and inthe reverse movement these parts vare brought together. I claim `asmy invention 1. A chuck comprlsing a .spindle member 30 of the outer sleeve 'member onthe spindle a corresponding `move' the shell in the direction for having va generallycylindrical body pQI'OIl,

the-.Outer end f .50.

an'fenlargement adacent the said body portion, 'and a head portion'at l' thejguter end, a shell in closing the said body portionandhead portion, and havinginternal inclined. ways at the outer end, jaws positioned in the, said ways, and engaged the vsaid-head portion, a sleeve member f i vfitting over the said body portion', opposed to the said enlargement, and xedly l'con-x nected tothe said shell, andv the opposed.

faces of the said sleeve member andenlargef k ment being in the-.form of ahelix.-

2.' A chuck comprising aspindle member havinga cylindrical vbody portion provided;

with a relatively fine thread on the periph;

ery and jaw engaglng means at the outer end, a shell linclosingthesaid body portion.. i.

in spaced relation `thereto, and having jaw engaging means at the outer end, jaws/,enf gaged with the said shell and spindle' mem-,

the said sleeve members being securedtd the inner'endgof the said shell and being a 'sliding fit for the said'body portion, the other of the said thread, and having a transverse slot in' the side wall, a pinextending radially 4from thc side of the said body lfportiorrand 'positioned in the said slot and the said lsleeve members' 80y having the opposed faces'formed suitably to' coperate as end cams.

3. A chuck comprising a spindle'member having an enlargement adjacent the free end and a shell member fitting the said venlargc h4 cam faces.

' I FRANK COBEY. Witnesses: 1 i M- ARTHUR E. BOWERS,

-LnzrHER F. TURNER.

sleeve members "havingla 7 51 thread engaged with thesaid-relatively fineV` the said enlargement aol' 

